Based on the supporting project of a certain plot of land in Yuhang District,Hangzhou,it focuses on the design and research of the enclosure scheme for the deep foundation pit involved in the construction of the box culvert and revetment structure of the existing river on North Shuixiang Road.The main difficulty lies in the fact that the foundation pit is located directly above the L3,L5 and L16 section tunnels of Hangzhou's rail transit,and the bottom of the foundation pit is only 5.0 m away from the nearest section tunnel.The research adopts the combination of MJS construction method piles and IMS construction method piles for combined pit bottom reinforcement and foundation pit enclosure measures.At the same time,based on the current terrain conditions,the excavation area is finely divided into grids and a reasonable excavation sequence is proposed,aiming to control the unloading ratio of the soil above the rail transit section tunnel and minimize the disturbance to the tunnel,effectively controlling the deformation of the section.Further design verification is conducted by establishing 3D numerical models of equally proportioned foundation pits and rail transit tunnels.Based on the numerical simulation results,the impact of foundation pit excavation on rail transit tunnels is controllable.
interval tunnelclose distancedeep&large foundation pitcombination reinforcementsegment excavation
万方数据
维普
